In vitro metabolism of helenalin and its inhibitory effect on human cytochrome P450 activity
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11160%2F22%3A10449935" target="_blank" >RIV/00216208:11160/22:10449935 - isvavai.cz</a>
Result on the web
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Fz8DfomZWv" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Fz8DfomZWv</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1007/s00204-021-03218-6" target="_blank" >10.1007/s00204-021-03218-6</a>
Alternative languages
Result language
angličtina
Original language name
In vitro metabolism of helenalin and its inhibitory effect on human cytochrome P450 activity
Original language description
Sesquiterpene lactone helenalin is used as an antiphlogistic in European and Chinese folk medicine. The pharmacological activities of helenalin have been extensively investigated, yet insufficient information exists about its metabolic properties. The objectives of the present study were (1) to investigate the in vitro NADPH-dependent metabolism of helenalin (5 and 100 mu M) using human and rat liver microsomes and liver cytosol, (2) to elucidate the role of human cytochrome P450 (CYP) enzymes in its oxidative metabolism, and (3) to study the inhibition of human CYPs by helenalin. Five oxidative metabolites were detected in NADPH-dependent human and rat liver microsomal incubations, while two reduced metabolites were detected only in NADPH-dependent human microsomal and cytosolic incubations. In human liver microsomes, the main oxidative metabolite was 14-hydroxyhelenalin, and in rat liver microsomes 9-hydroxyhelenalin. The overall oxidation of helenalin was several times more efficient in rat than in human liver microsomes. In humans, CYP3A4 and CYP3A5 followed by CYP2B6 were the main enzymes responsible for the hepatic metabolism of helenalin. The extrahepatic CYP2A13 oxidized helenalin most efficiently among CYP enzymes, possessing the K(m) value of 0.6 mu M. Helenalin inhibited CYP3A4 (IC50 = 18.7 mu M) and CYP3A5 (IC50 = 62.6 mu M), and acted as a mechanism-based inhibitor of CYP2A13 (IC50 = 1.1 mu M, K(I) = 6.7 mu M, and k(inact) = 0.58 ln(%)/min). It may be concluded that the metabolism of helenalin differs between rats and humans, in the latter its oxidation is catalyzed by hepatic CYP2B6, CYP3A4, CYP3A5, and CYP3A7, and extrahepatic CYP2A13.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
30104 - Pharmacology and pharmacy
Result continuities
Project
<a href="/en/project/GA18-09946S" target="_blank" >GA18-09946S: Metabolism of terpenes and mechanisms of their toxic effects in human liver</a><br>
Continuities
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Others
Publication year
2022
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Archives of Toxicology
ISSN
0340-5761
e-ISSN
1432-0738
Volume of the periodical
96
Issue of the periodical within the volume
3
Country of publishing house
DE - GERMANY
Number of pages
16
Pages from-to
793-808
UT code for WoS article
000739741600001
EID of the result in the Scopus database
2-s2.0-85122481695